The present invention relates both to a new display device modularized by burying a light emitting device in an insulating material, and to a display unit produced by two-dimensionally arraying such display devices.
In the case of assembling an image display unit by arraying light emitting devices in a matrix, if the image display unit is a liquid crystal display (LCD) or a plasma display panel (PDP), then light emitting devices have been directly formed on a substrate, while if the image display unit is a light emitting diode (LED) display, then single LED packages are arrayed on a substrate. For example, in the case of producing an image display unit such as an LCD or PDP, device isolation is impossible from the viewpoint of its structure and, accordingly, devices generally have been formed, at the beginning of the production process, in such a manner as to be spaced from each other with a pitch equivalent to a pixel pitch of a final image display unit.
On the other hand, in the case of producing an LED display, LED chips have been packaged by taking out LED chips after dicing, and individually connecting the LED chips to external electrodes by wire-bonding or bump-connection using flip-chip. Since an LED (Light Emitting Diode) representative of a light emitting device is expensive, an image display unit using such LEDs can be produced at a low cost by producing a large number of LEDs from one wafer. More specifically, the cost of an image display unit can be lowered by reducing the size of an LED chip from an ordinary size, about 300 μm square to several ten μm square, packaging such small-sized LED chips, and producing the image display unit using the LED chips thus packaged.
As described above, the related art LED display has been produced by a method of mechanically arraying expensive modularized LED packages at a high density on a base body, and connecting an external electrode of each LED package to an electrode formed on the base body. Such a production method is disadvantageous in that since not only packaging of each LED requires a large production cost but also carrying of each LED or mounting thereof on a base body takes a lot of steps, the productivity and fabrication cost of the LED display are degraded.